Mechanisms to reduce the worst-case latency for ultra-low latency applications

ABSTRACT

This disclosure describes systems, methods, and devices related to latency reduction. The device may set up a plurality of links between an access point (AP) multi-link device (MLD) and a non-AP MLD. The device may encode a frame for transmission on a first link of the plurality of links between a first AP of the AP MLD and a first STA of the non-AP MLD. The device may identify an indication received at a second STA of the non-AP MLD using an interference mitigation signal. The device may cause to stop the transmission of the frame on the first link based on the indication. The device may identify a second frame on the first link received from the first AP. The device may cause to resume the transmission of the first frame on the first link.

TECHNICAL FIELD

This disclosure generally relates to systems and methods for wirelesscommunications and, more particularly, to mechanisms to reduce theworst-case latency for ultra-low latency applications.

BACKGROUND

Wireless devices are becoming widely prevalent and are increasinglyrequesting access to wireless channels. The Institute of Electrical andElectronics Engineers (IEEE) is developing one or more standards thatutilize Orthogonal Frequency-Division Multiple Access (OFDMA) in channelallocation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a network diagram illustrating an example network environmentfor latency reduction, in accordance with one or more exampleembodiments of the present disclosure.

FIG. 1B depicts an illustrative schematic diagram for a multi-linkdevice (MLD) between two logical entities, in accordance with one ormore example embodiments of the present disclosure.

FIG. 1C depicts an illustrative schematic diagram for a multi-linkdevice (MLD) between AP with logical entities and a non-AP with logicalentities, in accordance with one or more example embodiments of thepresent disclosure.

FIG. 2 depicts an illustrative schematic diagram for latency reduction,in accordance with one or more example embodiments of the presentdisclosure.

FIG. 3 depicts an illustrative schematic diagram for latency reduction,in accordance with one or more example embodiments of the presentdisclosure.

FIG. 3 depicts an illustrative schematic diagram for a control frame forlatency reduction, in accordance with one or more example embodiments ofthe present disclosure.

FIG. 5 depicts an illustrative schematic diagram for latency reduction,in accordance with one or more example embodiments of the presentdisclosure.

FIG. 6 depicts an illustrative schematic diagram for latency reduction,in accordance with one or more example embodiments of the presentdisclosure.

FIG. 7 depicts an illustrative schematic diagram for latency reduction,in accordance with one or more example embodiments of the presentdisclosure.

FIG. 8 depicts an illustrative schematic diagram for latency reduction,in accordance with one or more example embodiments of the presentdisclosure.

FIG. 9 depicts an illustrative schematic diagram for latency reduction,in accordance with one or more example embodiments of the presentdisclosure.

FIG. 10 depicts an illustrative schematic diagram for latency reduction,in accordance with one or more example embodiments of the presentdisclosure.

FIG. 11 illustrates a flow diagram of a process for an illustrativelatency reduction system, in accordance with one or more exampleembodiments of the present disclosure.

FIG. 12 illustrates a functional diagram of an exemplary communicationstation that may be suitable for use as a user device, in accordancewith one or more example embodiments of the present disclosure.

FIG. 13 illustrates a block diagram of an example machine upon which anyof one or more techniques (e.g., methods) may be performed, inaccordance with one or more example embodiments of the presentdisclosure.

FIG. 14 is a block diagram of a radio architecture in accordance withsome examples.

FIG. 15 illustrates an example front-end module circuitry for use in theradio architecture of FIG. 14, in accordance with one or more exampleembodiments of the present disclosure.

FIG. 16 illustrates an example radio IC circuitry for use in the radioarchitecture of FIG. 14, in accordance with one or more exampleembodiments of the present disclosure.

FIG. 17 illustrates an example baseband processing circuitry for use inthe radio architecture of FIG. 14, in accordance with one or moreexample embodiments of the present disclosure.

DETAILED DESCRIPTION

The following description and the drawings sufficiently illustratespecific embodiments to enable those skilled in the art to practicethem. Other embodiments may incorporate structural, logical, electrical,process, algorithm, and other changes. Portions and features of someembodiments may be included in or substituted for, those of otherembodiments. Embodiments set forth in the claims encompass all availableequivalents of those claims.

To increase the overall throughput of Wi-Fi devices, transmitopportunity (TXOP) and frame aggregation was introduced in 802.11n andsubsequent standards. This aggregation makes the PPDU data payload muchbigger and therefore occupies much longer airtime.

Although frame aggregation helps improve throughput and reduce averagelatency for a pair of STAs, it can result in a much higher worst-caselatency for a 3^(rd) party STA waiting for the wireless medium to beidle due to much longer airtime occupied by a long aggregated PPDUbetween the pair of STAs. Time-sensitive frames may experience a higherlatency if the channel is occupied by a long PPDU transmission by otherdevices from the same BSS or overlapping BSS (OBSS).

With the introduction of multiple link capability in 802.11be, thisproblem can be mitigated if a client device supports simultaneoustransmission and reception (STR) and if there is at least one link idle.However, this problem still exists if a client device is a non-STRdevice, which cannot simultaneously transmit and receive on 2 or morelinks.

In 802.11be, an MLD (multi-link device) is defined as follows: A devicethat is a logical entity and has more than one affiliated station (STA)and has a single medium access control (MAC) service access point (SAP)to logical link control (LLC), which includes one MAC data service.

In a BSS, an AP MLD (multi-link device) is a STR AP MLD, which cantransmit and receive frames over multiple links (i.e. channels), such aschannel 1 and channel 2, at the same time. There are STR non-AP MLDs andnon-STR non-AP MLDs. The STR non-AP MLD is able to transmit and receiveframes over multiple channels, such as channel 1 and channel 2, at thesame time. The non-STR non-AP MLD is only able to transmit or receiveframes over channel 1 and channel 2 at the same time but cannot transmitand receive frames on channel 1 and channel 2 simultaneously.

It is proposed to control the TXOP length to be less than a certainvalue to solve this problem, however, it is at the cost of throughputloss. This proposal can reduce the worst-case latency for ultra-lowlatency applications. However, it is very inefficient in terms ofspectrum efficiency.

A solution is proposed to solve the problem in this scenario. However,on the other hand, if both of the two channels are occupied by anyongoing transmission from the same or overlapping BSS (OBSS), thisproblem still exists.

In 802.11, to improve the overall throughput and latency of Wi-Fidevices, multi-user (MU) OFDMA was introduced in 802.11ax. OFDMA isideal for low-bandwidth, small-packet applications such as IoT sensors,controllers, etc. In the Downlink phase, the AP can schedule the datatransmission to multiple users simultaneously using DL-MU-OFDMA while ithas downlink data packets for multiple users in the transmission queue.However, in the uplink phase, the AP needs to be aware of the bufferstatus of each STA for the following UL MU-OFDMA transmissionscheduling, which is obtained by AP sending a “buffer status report”trigger frame to multiple STAs. Upon reception of the trigger frame, theSTAs will feedback the buffer status report based on the queued UL data.Based on the buffer status report received from each STA, the APschedules the UL resource units for the UL MU OFDMA transmissions. Inorder to obtain the buffer status of each STA, the AP needs to triggereach STA with a certain periodicity, which could lead tounder-utilization of the resources and also increased latency.

Example embodiments of the present disclosure relate to systems,methods, and devices for Methods and mechanisms to reduce the worst-caselatency for ultra-low latency applications in Next Generation Wi-Fi.

In one or more embodiments, a latency reduction system may facilitatemechanisms to reduce the worst-case latency for ultra-low latencyapplications for non-STR non-AP MLD in 802.11be, which is expected to bethe majority of deployments.

In one or more embodiments, a latency reduction system may facilitatemechanisms to reduce the worst-case latency for ultra-low latencyapplications for small packets in Wi-Fi networks while all the operationchannels are being occupied by other STAs within the BSS or OBSS, whichis expected to be seen in high dense Wi-Fi deployed environment.

Low latency and reliable communications are some of the main gaps inexisting Wi-Fi radios (including 802.11ax) and there is an opportunityto address these problems in 802.11be or in WiFi8 (next gen Wi-Fi) withmultiple links or other new capabilities. The mechanisms proposed inthis disclosure will enable the low latency application for non-STRnon-AP MLD in 802.11be that is only able to transmit or receive a packetat the same time.

In one or more embodiments, a latency reduction system may define a newscheduling request signal, which is generated by ZC sequence and is onlyaround 10-20 microseconds long, to enable the STA to request to bescheduled faster for time-critical data that just arrived and also avoidthe spectrum under-utilization due to the periodic “buffer statusreport” trigger procedure in the UL MU OFDMA. It can enable the STA tobe scheduled faster for time-critical data that just arrived and alsoavoid the spectrum under-utilization due to the periodic “buffer statusreport” trigger procedure in the UL MU OFDMA.

The above descriptions are for purposes of illustration and are notmeant to be limiting. Numerous other examples, configurations,processes, algorithms, etc., may exist, some of which are described ingreater detail below. Example embodiments will now be described withreference to the accompanying figures.

FIG. 1A is a network diagram illustrating an example network environmentof latency reduction, according to some example embodiments of thepresent disclosure. Wireless network 100 may include one or more userdevices 120 and one or more access points(s) (AP) 102, which maycommunicate in accordance with IEEE 802.11 communication standards. Theuser device(s) 120 may be mobile devices that are non-stationary (e.g.,not having fixed locations) or may be stationary devices.

In some embodiments, the user devices 120 and the AP 102 may include oneor more computer systems similar to that of the functional diagram ofFIG. 12 and/or the example machine/system of FIG. 13.

One or more illustrative user device(s) 120 and/or AP(s) 102 may beoperable by one or more user(s) 110. It should be noted that anyaddressable unit may be a station (STA). An STA may take on multipledistinct characteristics, each of which shape its function. For example,a single addressable unit might simultaneously be a portable STA, aquality-of-service (QoS) STA, a dependent STA, and a hidden STA. The oneor more illustrative user device(s) 120 and the AP(s) 102 may be STAs.The one or more illustrative user device(s) 120 and/or AP(s) 102 mayoperate as a personal basic service set (PBSS) control point/accesspoint (PCP/AP). The user device(s) 120 (e.g., 124, 126, or 128) and/orAP(s) 102 may include any suitable processor-driven device including,but not limited to, a mobile device or a non-mobile, e.g., a staticdevice. For example, user device(s) 120 and/or AP(s) 102 may include, auser equipment (UE), a station (STA), an access point (AP), a softwareenabled AP (SoftAP), a personal computer (PC), a wearable wirelessdevice (e.g., bracelet, watch, glasses, ring, etc.), a desktop computer,a mobile computer, a laptop computer, an ultrabook™ computer, a notebookcomputer, a tablet computer, a server computer, a handheld computer, ahandheld device, an internet of things (IoT) device, a sensor device, aPDA device, a handheld PDA device, an on-board device, an off-boarddevice, a hybrid device (e.g., combining cellular phone functionalitieswith PDA device functionalities), a consumer device, a vehicular device,a non-vehicular device, a mobile or portable device, a non-mobile ornon-portable device, a mobile phone, a cellular telephone, a PCS device,a PDA device which incorporates a wireless communication device, amobile or portable GPS device, a DVB device, a relatively smallcomputing device, a non-desktop computer, a “carry small live large”(CSLL) device, an ultra mobile device (UMD), an ultra mobile PC (UMPC),a mobile internet device (MID), an “origami” device or computing device,a device that supports dynamically composable computing (DCC), acontext-aware device, a video device, an audio device, an A/V device, aset-top-box (STB), a blu-ray disc (BD) player, a BD recorder, a digitalvideo disc (DVD) player, a high definition (HD) DVD player, a DVDrecorder, a HD DVD recorder, a personal video recorder (PVR), abroadcast HD receiver, a video source, an audio source, a video sink, anaudio sink, a stereo tuner, a broadcast radio receiver, a flat paneldisplay, a personal media player (PMP), a digital video camera (DVC), adigital audio player, a speaker, an audio receiver, an audio amplifier,a gaming device, a data source, a data sink, a digital still camera(DSC), a media player, a smartphone, a television, a music player, orthe like. Other devices, including smart devices such as lamps, climatecontrol, car components, household components, appliances, etc. may alsobe included in this list.

As used herein, the term “Internet of Things (IoT) device” is used torefer to any object (e.g., an appliance, a sensor, etc.) that has anaddressable interface (e.g., an Internet protocol (IP) address, aBluetooth identifier (ID), a near-field communication (NFC) ID, etc.)and can transmit information to one or more other devices over a wiredor wireless connection. An IoT device may have a passive communicationinterface, such as a quick response (QR) code, a radio-frequencyidentification (RFID) tag, an NFC tag, or the like, or an activecommunication interface, such as a modem, a transceiver, atransmitter-receiver, or the like. An IoT device can have a particularset of attributes (e.g., a device state or status, such as whether theIoT device is on or off, open or closed, idle or active, available fortask execution or busy, and so on, a cooling or heating function, anenvironmental monitoring or recording function, a light-emittingfunction, a sound-emitting function, etc.) that can be embedded inand/or controlled/monitored by a central processing unit (CPU),microprocessor, ASIC, or the like, and configured for connection to anIoT network such as a local ad-hoc network or the Internet. For example,IoT devices may include, but are not limited to, refrigerators,toasters, ovens, microwaves, freezers, dishwashers, dishes, hand tools,clothes washers, clothes dryers, furnaces, air conditioners,thermostats, televisions, light fixtures, vacuum cleaners, sprinklers,electricity meters, gas meters, etc., so long as the devices areequipped with an addressable communications interface for communicatingwith the IoT network. IoT devices may also include cell phones, desktopcomputers, laptop computers, tablet computers, personal digitalassistants (PDAs), etc. Accordingly, the IoT network may be comprised ofa combination of “legacy” Internet-accessible devices (e.g., laptop ordesktop computers, cell phones, etc.) in addition to devices that do nottypically have Internet-connectivity (e.g., dishwashers, etc.).

The user device(s) 120 and/or AP(s) 102 may also include mesh stationsin, for example, a mesh network, in accordance with one or more IEEE802.11 standards and/or 3GPP standards.

Any of the user device(s) 120 (e.g., user devices 124, 126, 128), andAP(s) 102 may be configured to communicate with each other via one ormore communications networks 130 and/or 135 wirelessly or wired. Theuser device(s) 120 may also communicate peer-to-peer or directly witheach other with or without the AP(s) 102. Any of the communicationsnetworks 130 and/or 135 may include, but not limited to, any one of acombination of different types of suitable communications networks suchas, for example, broadcasting networks, cable networks, public networks(e.g., the Internet), private networks, wireless networks, cellularnetworks, or any other suitable private and/or public networks. Further,any of the communications networks 130 and/or 135 may have any suitablecommunication range associated therewith and may include, for example,global networks (e.g., the Internet), metropolitan area networks (MANs),wide area networks (WANs), local area networks (LANs), or personal areanetworks (PANs). In addition, any of the communications networks 130and/or 135 may include any type of medium over which network traffic maybe carried including, but not limited to, coaxial cable, twisted-pairwire, optical fiber, a hybrid fiber coaxial (HFC) medium, microwaveterrestrial transceivers, radio frequency communication mediums, whitespace communication mediums, ultra-high frequency communication mediums,satellite communication mediums, or any combination thereof.

Any of the user device(s) 120 (e.g., user devices 124, 126, 128) andAP(s) 102 may include one or more communications antennas. The one ormore communications antennas may be any suitable type of antennascorresponding to the communications protocols used by the user device(s)120 (e.g., user devices 124, 126 and 128), and AP(s) 102. Somenon-limiting examples of suitable communications antennas include Wi-Fiantennas, Institute of Electrical and Electronics Engineers (IEEE)802.11 family of standards compatible antennas, directional antennas,non-directional antennas, dipole antennas, folded dipole antennas, patchantennas, multiple-input multiple-output (MIMO) antennas,omnidirectional antennas, quasi-omnidirectional antennas, or the like.The one or more communications antennas may be communicatively coupledto a radio component to transmit and/or receive signals, such ascommunications signals to and/or from the user devices 120 and/or AP(s)102.

Any of the user device(s) 120 (e.g., user devices 124, 126, 128), andAP(s) 102 may be configured to perform directional transmission and/ordirectional reception in conjunction with wirelessly communicating in awireless network. Any of the user device(s) 120 (e.g., user devices 124,126, 128), and AP(s) 102 may be configured to perform such directionaltransmission and/or reception using a set of multiple antenna arrays(e.g., DMG antenna arrays or the like). Each of the multiple antennaarrays may be used for transmission and/or reception in a particularrespective direction or range of directions. Any of the user device(s)120 (e.g., user devices 124, 126, 128), and AP(s) 102 may be configuredto perform any given directional transmission towards one or moredefined transmit sectors. Any of the user device(s) 120 (e.g., userdevices 124, 126, 128), and AP(s) 102 may be configured to perform anygiven directional reception from one or more defined receive sectors.

MIMO beamforming in a wireless network may be accomplished using RFbeamforming and/or digital beamforming. In some embodiments, inperforming a given MIMO transmission, user devices 120 and/or AP(s) 102may be configured to use all or a subset of its one or morecommunications antennas to perform MIMO beamforming.

Any of the user devices 120 (e.g., user devices 124, 126, 128), andAP(s) 102 may include any suitable radio and/or transceiver fortransmitting and/or receiving radio frequency (RF) signals in thebandwidth and/or channels corresponding to the communications protocolsutilized by any of the user device(s) 120 and AP(s) 102 to communicatewith each other. The radio components may include hardware and/orsoftware to modulate and/or demodulate communications signals accordingto pre-established transmission protocols. The radio components mayfurther have hardware and/or software instructions to communicate viaone or more Wi-Fi and/or Wi-Fi direct protocols, as standardized by theInstitute of Electrical and Electronics Engineers (IEEE) 802.11standards. In certain example embodiments, the radio component, incooperation with the communications antennas, may be configured tocommunicate via 2.4 GHz channels (e.g. 802.11b, 802.11g, 802.11n,802.11ax), 5 GHz channels (e.g. 802.11n, 802.11ac, 802.11ax, 802.11be,etc.), 6 GHz channels (e.g., 802.11ax, 802.11be, etc.), or 60 GHZchannels (e.g. 802.11ad, 802.11ay). 800 MHz channels (e.g. 802.11ah).The communications antennas may operate at 28 GHz and 40 GHz. It shouldbe understood that this list of communication channels in accordancewith certain 802.11 standards is only a partial list and that other802.11 standards may be used (e.g., Next Generation Wi-Fi, or otherstandards). In some embodiments, non-Wi-Fi protocols may be used forcommunications between devices, such as Bluetooth, dedicated short-rangecommunication (DSRC), Ultra-High Frequency (UHF) (e.g. IEEE 802.11af,IEEE 802.22), white band frequency (e.g., white spaces), or otherpacketized radio communications. The radio component may include anyknown receiver and baseband suitable for communicating via thecommunications protocols. The radio component may further include a lownoise amplifier (LNA), additional signal amplifiers, ananalog-to-digital (A/D) converter, one or more buffers, and digitalbaseband.

In one embodiment, and with reference to FIG. 1A, a user device 120 maybe in communication with one or more APs 102. For example, one or moreAPs 102 may implement a latency reduction 142 with one or more userdevices 120. The one or more APs 102 may be multi-link devices (MLDs)and the one or more user device 120 may be non-AP MLDs. Each of the oneor more APs 102 may comprise a plurality of individual APs (e.g., AP1,AP2, . . . , APn, where n is an integer) and each of the one or moreuser devices 120 may comprise a plurality of individual STAs (e.g.,STA1, STA2, . . . , STAn). The AP MLDs and the non-AP MLDs may set upone or more links (e.g., Link1, Link2, . . . , Linkn) between each ofthe individual APs and STAs. It is understood that the abovedescriptions are for purposes of illustration and are not meant to belimiting.

FIG. 1B depicts an illustrative schematic diagram for two multi-linkdevices (MLDs), in accordance with one or more example embodiments ofthe present disclosure.

Referring to FIG. 1B, there are shown two MLDs, where each MLD includesmultiple STAs that can set up links with each other. An MLD may be alogical entity that contains one or more STAs. The MLD has one MAC dataservice interface and primitives to the logical link control (LLC) and asingle address associated with the interface, which can be used tocommunicate on the distribution system medium (DSM). It should be notedthat an MLD allows STAs within the MLD to have the same MAC address. Itshould also be noted that the exact name can be changed.

In this example of FIG. 1B, the MLD 1 and MLD 2 may be two separatephysical devices, where each one comprises a number of virtual orlogical devices. For example, MLD 1 may comprise three STAs, STA1.1,STA1.2, and STA1.3 and MLD 2 that may comprise three STAs, STA2.1,STA2.2, and STA2.3. The example shows that logical device STA1.1 iscommunicating with logical device STA2.1 over link 1, that logicaldevice STA1.2 is communicating with logical device STA2.2 over link 2,and that device STA1.3 is communicating with logical device STA2.3 overlink 3.

FIG. 1C depicts an illustrative schematic diagram for an AP MLD and anon-AP MLD, in accordance with one or more example embodiments of thepresent disclosure.

Referring to FIG. 1C, there are shown two MLDs on either side whichincludes multiple STAs that can set up links with each other. Forinfrastructure framework, the AP MLD may include APs (e.g., AP1, AP2,and AP3) on one side, and the non-AP MLD may include non-AP STAs (STA1,STA2, and STA3) on the other side. The detailed definition is shownbelow. AP MLD is a multi-link logical entity, where each STA within theMLD is an EHT AP. Non-AP MLD is a multi-link logical entity, where eachSTA within the multi-link logical entity is a non-AP EHT STA. It shouldbe noted that this framework is a natural extension from the one linkoperation between two STAs, which are AP and non-AP STA under theinfrastructure framework (e.g., when an AP is used as a medium forcommunication between STAs).

In the example of FIG. 1C, the AP MLD and non-AP MLD may be two separatephysical devices, where each one comprises a number of virtual orlogical devices. For example, the AP MLD may comprise three APs, AP1operating on 2.4 GHz, AP2 operating on 5 GHz, and AP3 operating on 6GHz. Further, the non-AP MLD may comprise three non-AP STAs, STA1communicating with AP1 on link 1, STA2 communicating with AP2 on link 2,and STA3 communicating with AP3 on link 3. It should be understood thatthese are only examples and that more or less entities may be includedin an MLD.

The AP MLD is shown in FIG. 1C to have access to a distribution system(DS), which is a system used to interconnect a set of BSSs to create anextended service set (ESS). The AP MLD is also shown in FIG. 1C to haveaccess a distribution system medium (DSM), which is the medium used by aDS for BSS interconnections. Simply put, DS and DSM allow the AP MLD tocommunicate with different BSSs.

It should be understood that although the example shows three logicalentities within the AP MLD and the three logical entities within thenon-AP MLD, this is merely for illustration purposes and that othernumbers of logical entities with each of the AP MLD and non-AP MLD maybe envisioned.

FIG. 2 depicts an illustrative schematic diagram for an ultra-lowlatency packet, in accordance with one or more example embodiments ofthe present disclosure.

Referring to FIG. 2, there is shown an ultra-low latency packet cannotbe transmitted during an uplink transmission from a STA of a non-AP MLD.

As shown in the following FIG. 2, while a STA of a non-STR non-AP MLD,such as STA1, is sending an uplink data packet to the AP of an AP MLDover one of the operation channels, such as channel 1, a time-criticalpacket may arrive at the AP MLD for the non-AP MLD. Even though AP2 ofthe AP MLD is able to access another operation channel, channel 2, andsend the time-critical packet to STA2, it is impossible for STA2 todecode the downlink packet successfully due to large self-interference(interference power could be as large as −13 dBm) that is generated fromthe uplink transmission from STA1 to the AP1 over channel 1. Therefore,the time-critical packet can only be transmitted to the non-AP MLD afterthe completion of the current uplink transmission with a long TXOPlength (e.g., 5 milliseconds).

In one or more embodiments, a latency reduction system may facilitatenew mechanisms to solve this problem by using an interference mitigationtechnique such as the Zadoff-Chu sequence.

In one or more embodiments, a latency reduction system may facilitatethat an AP MLD is a STR AP MLD, which can transmit and receive framesover multiple channels, such as channel 1 and channel 2, at the sametime. It is assumed that a non-AP MLD is a non-STR non-AP MLD that isonly able to transmit or receive frames over channel 1 and/or channel 2at the same time and cannot transmit and receive frames over channel 1and channel 2 simultaneously.

While the AP MLD is receiving an uplink packet from one of its non-STRnon-AP MLD over channel 1, such as STA1, and a time-critical packetarrives at the AP MLD for the non-AP MLD, it will use the following twomethods to send the time-critical packet to the non-AP MLD. It isunderstood that the above descriptions are for purposes of illustrationand are not meant to be limiting.

FIG. 3 depicts an illustrative schematic diagram for a control frame forlatency reduction, in accordance with one or more example embodiments ofthe present disclosure.

Referring to FIG. 3, there is shown an SR (stop-request) control frameis encoded in a ZC sequence.

As shown in FIG. 3, the AP MLD sends a stop request (SR) control frameusing a sequence, such as a ZC (Zadoff-Chu) sequence, that can mitigateinterference from STA1 to STA2 of the non-AP MLD over channel 2. This SRcontrol frame using the ZC sequence is used to indicate the receiver tostop the frame transmission (e.g., frame being comprised of a preamble anumber of MAC protocol data units (MPDUs)) on another channel, such aschannel 1 in this example. This rule is pre-negotiated between the APMLD and the non-AP MLD.

As a result, upon detection of the SR control frame on channel 2 withthe ZC sequence which is assigned to STA1 by the AP MLD, STA1 of thenon-AP MLD stops the current uplink transmission over channel 1. STA1may stop the transmission after completing the current MPDUtransmission.

Then, the AP1 of the AP MLD accesses channel 1 to send the time-criticalpacket (ultra-low latency packet) to STA1 of the non-AP MLD PIFS or SIFStime after the end of the current uplink transmission (e.g., MPDU1).

Upon reception of the time-critical packet from AP1, STA1 responds withan ACK frame and then continues the uplink transmission SIFS time afterthe transmission of the ACK frame as shown in FIG. 3.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 4 depicts an illustrative schematic diagram for an ultra-lowlatency packet, in accordance with one or more example embodiments ofthe present disclosure.

Referring to FIG. 4, there is shown an ultra-low latency packet isencoded using a ZC sequence.

As shown in FIG. 4, instead of transmitting a SR control frame using aZC sequence as shown in Method 1, AP2 of the AP MLD sends the shorttime-critical packet encoded using a ZC sequence to STA2 over channel 2.Upon the reception of the downlink time-critical packet from AP2 using aZC sequence, STA2 responds with an acknowledgment to AP2.

To reduce power consumption for the ZC detection, a STA may only turn onthe detection block periodically for a fixed time period while the STAis sending uplink data to the AP over another channel.

A ZC sequence of length N with root, μ, is defined as:

${z_{0} = \begin{bmatrix}z_{0} \\z_{1} \\\vdots \\z_{N - 1}\end{bmatrix}},{with}$${z_{i} = {{e^{\frac{j\;{\mu\pi}\; i^{2}}{N}}\mspace{14mu}{for}\mspace{14mu} i} = 0}},1,\ldots\;,{N - 1}$

In multi-user case, each non-STR non-AP MLD can be assigned a ZCsequence of length N with same root, μ, but different shift Δ, z_(Δ),defined as:

${z_{\Delta = 1} = \begin{bmatrix}z_{N - 1} \\z_{0} \\z_{1} \\\vdots \\z_{N - 2}\end{bmatrix}},{z_{\Delta = 1} = \begin{bmatrix}z_{N - 2} \\z_{N - 1} \\z_{0} \\\vdots \\z_{N - 3}\end{bmatrix}},{z_{\Delta = {N - 1}} = \begin{bmatrix}z_{1} \\z_{2} \\z_{3} \\\vdots \\z_{0}\end{bmatrix}}$

The orthogonal property between z_(i) and z_(j) with different shiftsenables the receiver to identify whether the ZC sequence signal is forit or not.

${z_{i}^{H}z_{j}} = \left\{ \begin{matrix}{1,{i = j}} \\{0,{i \neq j}}\end{matrix} \right.$

However, to avoid interference between the multi-users, the shift Δamong different users should be large enough to mitigate the effect fromthe delay spread.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 5 depicts an illustrative schematic diagram for latency reduction,in accordance with one or more example embodiments of the presentdisclosure.

As shown in FIG. 5, while the channel is occupied by other STAs withinthe BSS or OBSS STAs, the STR AP MLD, the STR STA MLD or non-STR STA MLDare not able to access any channel or empty any channel for thetime-critical packet transmission.

In one or more embodiments, a latency reduction system may facilitatenew mechanisms to solve the problem while the channel is occupied byOBSS or non-AP MLDs within the same BSS through using an interfacemitigation technique such as the Zadoff-Chu sequence. Note: thisapproach can also be used in the non-802.11be devices as long as itsupports ultra-low latency (ULL) packet generation and detection usingZC sequence.

It is assumed that the AP MLD or the non-AP MLD those havingtime-critical applications have the Zadoff Chu sequence generation anddetection capability.

To reduce power consumption for the ZC detection, a STA may only turn onthe detection block periodically for a fixed time period while the STAis aware of ongoing long TXOP data transmission, which is not for it.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 6 depicts an illustrative schematic diagram for latency reduction,in accordance with one or more example embodiments of the presentdisclosure.

As shown in FIG. 6, while all the operation channels are occupied by theOBSS devices or another device within the BSS and a time-critical packetarrives at the AP MLD or non-AP MLD, the AP MLD or non-AP MLD will sendthe time-critical packet using ZC sequence to the non-AP MLD or the APMLD over the operation channel for ZC sequence detection. It isunderstood that the above descriptions are for purposes of illustrationand are not meant to be limiting.

FIG. 7 depicts an illustrative schematic diagram for a design of atime-critical packet, in accordance with one or more example embodimentsof the present disclosure.

Referring to FIG. 7, there is shown a design of a time-critical packet.

z_(Δ) ₀ and z_(Δ) ₁ are defined with a fixed shift in the same BSS usedto identify different BSS and packet acquisition of the time-criticalpacket sent using ZC sequence. It can be reused in non-overlapping BSS.If two neighbor BSSs operating at the same channel, z_(Δ) ₀ and z_(Δ) ₁with different shifts or different root values should be used toidentify whether it is sent from the current BSS or not.

z_(Δ) ₂ and z_(Δ) ₃ are used to identify different users in the sameBSS. If the number of users in the same BSS is small, a single ZCsequence z_(Δ) ₂ with different shifts will be used to identifydifferent users in the same BSS. If the number of users in the same BSSis large and cannot be supported by a single ZC sequence, two or more ZCsequences with shifts can be used to support more users.

For the non-AP MLD or AP MLD, while detecting the first two ZC sequencesas z_(Δ) ₀ and z_(Δ) ₁ , and the third (and fourth) ZC sequence as z_(Δ)₂ (and z_(Δ) ₃ ), which is assigned for this non-AP MLD, indicates thestarting of the time-critical packet from or to this non-AP MLD.

The ZC sequence following z_(Δ) ₂ and z_(Δ) ₃ , z_(Δ) _(s) is used toindicate the sequence number of the transmitted packet. For example,z_(Δ) _(s) with Δ_(s) the shift means that the sequence number for thecurrent packet is Δ_(s). Note, it can be extended to two ZC sequencesfor a larger range of sequence numbers. However, it needs to bepredefined in the network as the identification of the STA in the BSSwith a single ZC sequence or two or more ZC sequences.

The payload following z_(Δ) _(s) is generated with z_(Δ) _(i) and z_(Δ)_(j) . Each bit of the payload will be defined as:

$b_{i} = \left\{ \begin{matrix}{1,{z_{\Delta_{i}}\mspace{14mu}{is}\mspace{14mu}{sent}\mspace{14mu}{over}\mspace{14mu}{this}\mspace{14mu}{symbol}}} \\{0,{z_{\Delta_{j}}\mspace{14mu}{is}\mspace{14mu}{sent}\mspace{14mu}{over}\mspace{14mu}{this}\mspace{14mu}{symbol}}}\end{matrix} \right.$

z_(Δ) _(i) and z_(Δ) _(j) are predefined by the AP and known to all theSTAs. Therefore, all the STAs and AP are able to decode the payload.

This approach can also be used in the non-802.11be devices as long asthe device supports ULL packet generation and detection using ZCsequence. It is understood that the above descriptions are for purposesof illustration and are not meant to be limiting.

FIG. 8 depicts an illustrative schematic diagram for latency reduction,in accordance with one or more example embodiments of the presentdisclosure.

Referring to FIG. 8, there is shown scheduling request signal formatusing ZC sequences.

Scheduling request signal generated with ZC sequence can be reused inthe Wi-Fi to support low latency applications.

The scheduling request signal will be generated with two extra ZCsequences with fixed shift for all the STAs in the same BSS andfollowing a single or more than two ZC sequences with different shiftsfor each STA as shown in FIG. 8, where,

z_(Δ) ₀ and z_(Δ) ₁ are defined with a fixed shift in the same BSS usedto identify different BSS and packet acquisition of the schedulingrequest signal. It can be reused in non-overlapping BSS. If two neighborBSSs operating at the same channel, z_(Δ) ₀ and z_(Δ) ₁ with differentshifts or different root values should be used.

z_(Δ) ₂ and z_(Δ) ₃ are used to identify different users in the sameBSS. If the number of users in the same BSS is small, a single ZCsequence z_(Δ) ₂ with different shifts will be used to identifydifferent users in the same BSS. If the number of users in the same BSSis large and cannot be supported by a single ZC sequence, two or more ZCsequences with shifts can be used to support more users. But this needsto be pre-defined and known to both the AP and STAs.

Note, the more ZC sequences following the two fixed ZC sequences areused to generate SR signal for each user, the better detectionperformance can be achieved especially under challenging channelconditions with severe interference, but it is at the cost of higherdetection complexity. Therefore, while the number of STAs in the BSS issmall, the scheduling request signal generated with z_(Δ) ₀ , z_(Δ) ₁and z_(Δ) ₂ , which can support up to N STAs in the BSS, may be is abetter choice in terms of the detection complexity. However, thescheduling request signal generated with z_(Δ) ₀ , z_(Δ) ₁ , z_(Δ) ₂ andz_(Δ) ₄ or even more ZC sequences are required to improve the detectionperformance while facing bad channel condition or larger interference.Here N is the length of the ZC sequence.

FIG. 9 depicts an illustrative schematic diagram for latency reduction,in accordance with one or more example embodiments of the presentdisclosure.

Referring to FIG. 9, there is shown uplink (UL) multi-user (MU) OFDMAtransmission with a new SR signal design.

In an example, it is assumed that the AP has ZC sequence detectioncapability. Each STA in the same BSS will be assigned a uniquescheduling request signal by the AP.

As shown in FIG. 9, while the STA1 or STA2 has a scheduling request, itwill send the SR signal using the ZC sequence assigned for it. It canfollow current 802.11 sensing before sending channel access policy oraccess the channel directly due to the negligible interference effect,which is only 3-4 OFDM symbols, to the ongoing normal Wi-Fi frametransmission.

Upon the detection of the scheduling request signal and identificationof the transmitter, the AP will send a trigger fame to the related STAsto collect buffer status information for scheduling the following UL MUOFDMA data transmission. It is understood that the above descriptionsare for purposes of illustration and are not meant to be limiting.

FIG. 10 depicts an illustrative schematic diagram for latency reduction,in accordance with one or more example embodiments of the presentdisclosure.

In one or more embodiments, an AP may use only SR signals received fromSTAs to schedule RUs without transmitting a BSRP Trigger frame. The APmay schedule a small RU to each STA from which it received a SR signalin a Basic Trigger frame to solicit uplink data frames. In the uplinkdata frames, the STAs may include a buffer status report. Based on thebuffer status report in the uplink data frames, the AP schedules moreaccurate RUs to the STAs in the next Basic Trigger frame.

The SR signal may indicate different levels of scheduling requests fordifferent STAs, it can be by pre-negotiation between the AP and the STAto set up the requested service flow characteristics, so the AP alreadyknows how to schedule that specific STA. It can include one or severalbits in the SR signal to indicate it needs to be scheduled for a singleframe or some simple indication of the requested service. For example,if two levels are to be defined, which request to be scheduled directlyor to be triggered for BSR. One extra ZC sequence can be used followingthe ZC sequence for identification of STA in the BSS to indicate therequest as shown in FIG. 10. This can be differentiated with two ZCsequences with different shift values, such as z_(i) and z_(i), i≠j.

AP should indicate whether it supports this feature or not in the beaconframe. STA should also indicate whether it supports this feature or notwhen it setups the association with the AP. The SR signal can also betransmitted on top of ongoing data transmission without contention. Itis understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 11 illustrates a flow diagram of illustrative process 1100 for alatency reduction system, in accordance with one or more exampleembodiments of the present disclosure.

At block 1102, a device (e.g., the user device(s) 120 and/or the AP 102of FIG. 1A and/or the latency reduction device 1319 of FIG. 13) mayestablish a multi-link operation with an AP MLD, wherein the AP MLDcomprises a plurality of APs within the AP MLD. The non-AP MLD is anon-simultaneous transmit receive (STR) device.

At block 1104, the device may set up a plurality of links between the APMLD and the non-AP MLD, wherein the multi-link operation connects oneach link of the plurality of links a respective AP of the AP MLD with arespective device of the non-AP MLD.

At block 1106, the device may encode a first frame for transmission on afirst link of the plurality of links between a first AP of the AP MLDand a first STA of the non-AP MLD.

At block 1108, the device may identify an indication received at asecond STA of the non-AP MLD using an interference mitigation signal.The first frame includes a first preamble and a number of medium accesscontrol (MAC) protocol data units (MPDUs). The indication includes apacket destined to the second STA on the second link. The packet isreceived on the second link without stopping transmission on the firstlink The indication is a stop request and wherein the interferencemitigation signal is a Zadoff-Chu sequence (ZC) sequence. The ZCsequence has a characteristic of z^(i) _(H)z_(j)=0, i≠j.

At block 1110, the device may cause to stop the transmission of theframe on the first link based on the indication.

At block 1112, the device may identify a second frame on the first linkreceived from the first AP.

At block 1114, the device may cause to resume the transmission of thefirst frame on the first link. Resuming the transmission includes addinga second preamble to remaining MPDUs of the first frame. The device maycause to send an acknowledgement to the second frame. The device mayperform cross-correlation to determine that the stop request is assignedto the first STA.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 12 shows a functional diagram of an exemplary communication station1200, in accordance with one or more example embodiments of the presentdisclosure. In one embodiment, FIG. 12 illustrates a functional blockdiagram of a communication station that may be suitable for use as an AP102 (FIG. 1A) or a user device 120 (FIG. 1A) in accordance with someembodiments. The communication station 1200 may also be suitable for useas a handheld device, a mobile device, a cellular telephone, asmartphone, a tablet, a netbook, a wireless terminal, a laptop computer,a wearable computer device, a femtocell, a high data rate (HDR)subscriber station, an access point, an access terminal, or otherpersonal communication system (PCS) device.

The communication station 1200 may include communications circuitry 1202and a transceiver 1210 for transmitting and receiving signals to andfrom other communication stations using one or more antennas 1201. Thecommunications circuitry 1202 may include circuitry that can operate thephysical layer (PHY) communications and/or medium access control (MAC)communications for controlling access to the wireless medium, and/or anyother communications layers for transmitting and receiving signals. Thecommunication station 1200 may also include processing circuitry 1206and memory 1208 arranged to perform the operations described herein. Insome embodiments, the communications circuitry 1202 and the processingcircuitry 1206 may be configured to perform operations detailed in theabove figures, diagrams, and flows.

In accordance with some embodiments, the communications circuitry 1202may be arranged to contend for a wireless medium and configure frames orpackets for communicating over the wireless medium. The communicationscircuitry 1202 may be arranged to transmit and receive signals. Thecommunications circuitry 1202 may also include circuitry formodulation/demodulation, upconversion/downconversion, filtering,amplification, etc. In some embodiments, the processing circuitry 1206of the communication station 1200 may include one or more processors. Inother embodiments, two or more antennas 1201 may be coupled to thecommunications circuitry 1202 arranged for sending and receivingsignals. The memory 1208 may store information for configuring theprocessing circuitry 1206 to perform operations for configuring andtransmitting message frames and performing the various operationsdescribed herein. The memory 1208 may include any type of memory,including non-transitory memory, for storing information in a formreadable by a machine (e.g., a computer). For example, the memory 1208may include a computer-readable storage device, read-only memory (ROM),random-access memory (RAM), magnetic disk storage media, optical storagemedia, flash-memory devices and other storage devices and media.

In some embodiments, the communication station 1200 may be part of aportable wireless communication device, such as a personal digitalassistant (PDA), a laptop or portable computer with wirelesscommunication capability, a web tablet, a wireless telephone, asmartphone, a wireless headset, a pager, an instant messaging device, adigital camera, an access point, a television, a medical device (e.g., aheart rate monitor, a blood pressure monitor, etc.), a wearable computerdevice, or another device that may receive and/or transmit informationwirelessly.

In some embodiments, the communication station 1200 may include one ormore antennas 1201. The antennas 1201 may include one or moredirectional or omnidirectional antennas, including, for example, dipoleantennas, monopole antennas, patch antennas, loop antennas, microstripantennas, or other types of antennas suitable for transmission of RFsignals. In some embodiments, instead of two or more antennas, a singleantenna with multiple apertures may be used. In these embodiments, eachaperture may be considered a separate antenna. In some multiple-inputmultiple-output (MIMO) embodiments, the antennas may be effectivelyseparated for spatial diversity and the different channelcharacteristics that may result between each of the antennas and theantennas of a transmitting station.

In some embodiments, the communication station 1200 may include one ormore of a keyboard, a display, a non-volatile memory port, multipleantennas, a graphics processor, an application processor, speakers, andother mobile device elements. The display may be an LCD screen includinga touch screen.

Although the communication station 1200 is illustrated as having severalseparate functional elements, two or more of the functional elements maybe combined and may be implemented by combinations ofsoftware-configured elements, such as processing elements includingdigital signal processors (DSPs), and/or other hardware elements. Forexample, some elements may include one or more microprocessors, DSPs,field-programmable gate arrays (FPGAs), application specific integratedcircuits (ASICs), radio-frequency integrated circuits (RFICs) andcombinations of various hardware and logic circuitry for performing atleast the functions described herein. In some embodiments, thefunctional elements of the communication station 1200 may refer to oneor more processes operating on one or more processing elements.

Certain embodiments may be implemented in one or a combination ofhardware, firmware, and software. Other embodiments may also beimplemented as instructions stored on a computer-readable storagedevice, which may be read and executed by at least one processor toperform the operations described herein. A computer-readable storagedevice may include any non-transitory memory mechanism for storinginformation in a form readable by a machine (e.g., a computer). Forexample, a computer-readable storage device may include read-only memory(ROM), random-access memory (RAM), magnetic disk storage media, opticalstorage media, flash-memory devices, and other storage devices andmedia. In some embodiments, the communication station 1200 may includeone or more processors and may be configured with instructions stored ona computer-readable storage device.

FIG. 13 illustrates a block diagram of an example of a machine 1300 orsystem upon which any one or more of the techniques (e.g.,methodologies) discussed herein may be performed. In other embodiments,the machine 1300 may operate as a standalone device or may be connected(e.g., networked) to other machines. In a networked deployment, themachine 1300 may operate in the capacity of a server machine, a clientmachine, or both in server-client network environments. In an example,the machine 1300 may act as a peer machine in peer-to-peer (P2P) (orother distributed) network environments. The machine 1300 may be apersonal computer (PC), a tablet PC, a set-top box (STB), a personaldigital assistant (PDA), a mobile telephone, a wearable computer device,a web appliance, a network router, a switch or bridge, or any machinecapable of executing instructions (sequential or otherwise) that specifyactions to be taken by that machine, such as a base station. Further,while only a single machine is illustrated, the term “machine” shallalso be taken to include any collection of machines that individually orjointly execute a set (or multiple sets) of instructions to perform anyone or more of the methodologies discussed herein, such as cloudcomputing, software as a service (SaaS), or other computer clusterconfigurations.

Examples, as described herein, may include or may operate on logic or anumber of components, modules, or mechanisms. Modules are tangibleentities (e.g., hardware) capable of performing specified operationswhen operating. A module includes hardware. In an example, the hardwaremay be specifically configured to carry out a specific operation (e.g.,hardwired). In another example, the hardware may include configurableexecution units (e.g., transistors, circuits, etc.) and a computerreadable medium containing instructions where the instructions configurethe execution units to carry out a specific operation when in operation.The configuring may occur under the direction of the executions units ora loading mechanism. Accordingly, the execution units arecommunicatively coupled to the computer-readable medium when the deviceis operating. In this example, the execution units may be a member ofmore than one module. For example, under operation, the execution unitsmay be configured by a first set of instructions to implement a firstmodule at one point in time and reconfigured by a second set ofinstructions to implement a second module at a second point in time.

The machine (e.g., computer system) 1300 may include a hardwareprocessor 1302 (e.g., a central processing unit (CPU), a graphicsprocessing unit (GPU), a hardware processor core, or any combinationthereof), a main memory 1304 and a static memory 1306, some or all ofwhich may communicate with each other via an interlink (e.g., bus) 1308.The machine 1300 may further include a power management device 1332, agraphics display device 1310, an alphanumeric input device 1312 (e.g., akeyboard), and a user interface (UI) navigation device 1314 (e.g., amouse). In an example, the graphics display device 1310, alphanumericinput device 1312, and UI navigation device 1314 may be a touch screendisplay. The machine 1300 may additionally include a storage device(i.e., drive unit) 1316, a signal generation device 1318 (e.g., aspeaker), a latency reduction device 1319, a network interfacedevice/transceiver 1320 coupled to antenna(s) 1330, and one or moresensors 1328, such as a global positioning system (GPS) sensor, acompass, an accelerometer, or other sensor. The machine 1300 may includean output controller 1334, such as a serial (e.g., universal serial bus(USB), parallel, or other wired or wireless (e.g., infrared (IR), nearfield communication (NFC), etc.) connection to communicate with orcontrol one or more peripheral devices (e.g., a printer, a card reader,etc.)). The operations in accordance with one or more exampleembodiments of the present disclosure may be carried out by a basebandprocessor. The baseband processor may be configured to generatecorresponding baseband signals. The baseband processor may furtherinclude physical layer (PHY) and medium access control layer (MAC)circuitry, and may further interface with the hardware processor 1302for generation and processing of the baseband signals and forcontrolling operations of the main memory 1304, the storage device 1316,and/or the latency reduction device 1319. The baseband processor may beprovided on a single radio card, a single chip, or an integrated circuit(IC).

The storage device 1316 may include a machine readable medium 1322 onwhich is stored one or more sets of data structures or instructions 1324(e.g., software) embodying or utilized by any one or more of thetechniques or functions described herein. The instructions 1324 may alsoreside, completely or at least partially, within the main memory 1304,within the static memory 1306, or within the hardware processor 1302during execution thereof by the machine 1300. In an example, one or anycombination of the hardware processor 1302, the main memory 1304, thestatic memory 1306, or the storage device 1316 may constitutemachine-readable media.

The latency reduction device 1319 may carry out or perform any of theoperations and processes (e.g., process 1100) described and shown above.

It is understood that the above are only a subset of what the latencyreduction device 1319 may be configured to perform and that otherfunctions included throughout this disclosure may also be performed bythe latency reduction device 1319.

While the machine-readable medium 1322 is illustrated as a singlemedium, the term “machine-readable medium” may include a single mediumor multiple media (e.g., a centralized or distributed database, and/orassociated caches and servers) configured to store the one or moreinstructions 1324.

Various embodiments may be implemented fully or partially in softwareand/or firmware. This software and/or firmware may take the form ofinstructions contained in or on a non-transitory computer-readablestorage medium. Those instructions may then be read and executed by oneor more processors to enable performance of the operations describedherein. The instructions may be in any suitable form, such as but notlimited to source code, compiled code, interpreted code, executablecode, static code, dynamic code, and the like. Such a computer-readablemedium may include any tangible non-transitory medium for storinginformation in a form readable by one or more computers, such as but notlimited to read only memory (ROM); random access memory (RAM); magneticdisk storage media; optical storage media; a flash memory, etc.

The term “machine-readable medium” may include any medium that iscapable of storing, encoding, or carrying instructions for execution bythe machine 1300 and that cause the machine 1300 to perform any one ormore of the techniques of the present disclosure, or that is capable ofstoring, encoding, or carrying data structures used by or associatedwith such instructions. Non-limiting machine-readable medium examplesmay include solid-state memories and optical and magnetic media. In anexample, a massed machine-readable medium includes a machine-readablemedium with a plurality of particles having resting mass. Specificexamples of massed machine-readable media may include non-volatilememory, such as semiconductor memory devices (e.g., electricallyprogrammable read-only memory (EPROM), or electrically erasableprogrammable read-only memory (EEPROM)) and flash memory devices;magnetic disks, such as internal hard disks and removable disks;magneto-optical disks; and CD-ROM and DVD-ROM disks.

The instructions 1324 may further be transmitted or received over acommunications network 1326 using a transmission medium via the networkinterface device/transceiver 1320 utilizing any one of a number oftransfer protocols (e.g., frame relay, internet protocol (IP),transmission control protocol (TCP), user datagram protocol (UDP),hypertext transfer protocol (HTTP), etc.). Example communicationsnetworks may include a local area network (LAN), a wide area network(WAN), a packet data network (e.g., the Internet), mobile telephonenetworks (e.g., cellular networks), plain old telephone (POTS) networks,wireless data networks (e.g., Institute of Electrical and ElectronicsEngineers (IEEE) 802.11 family of standards known as Wi-Fi®, IEEE 802.16family of standards known as WiMax®), IEEE 802.15.4 family of standards,and peer-to-peer (P2P) networks, among others. In an example, thenetwork interface device/transceiver 1320 may include one or morephysical jacks (e.g., Ethernet, coaxial, or phone jacks) or one or moreantennas to connect to the communications network 1326. In an example,the network interface device/transceiver 1320 may include a plurality ofantennas to wirelessly communicate using at least one of single-inputmultiple-output (SIMO), multiple-input multiple-output (MIMO), ormultiple-input single-output (MISO) techniques. The term “transmissionmedium” shall be taken to include any intangible medium that is capableof storing, encoding, or carrying instructions for execution by themachine 1300 and includes digital or analog communications signals orother intangible media to facilitate communication of such software.

The operations and processes described and shown above may be carriedout or performed in any suitable order as desired in variousimplementations. Additionally, in certain implementations, at least aportion of the operations may be carried out in parallel. Furthermore,in certain implementations, less than or more than the operationsdescribed may be performed.

FIG. 14 is a block diagram of a radio architecture 105A, 105B inaccordance with some embodiments that may be implemented in any one ofthe example APs 102 and/or the example STAs 120 of FIG. 1A. Radioarchitecture 105A, 105B may include radio front-end module (FEM)circuitry 1404 a-b, radio IC circuitry 1406 a-b and baseband processingcircuitry 1408 a-b. Radio architecture 105A, 105B as shown includes bothWireless Local Area Network (WLAN) functionality and Bluetooth (BT)functionality although embodiments are not so limited. In thisdisclosure, “WLAN” and “Wi-Fi” are used interchangeably.

FEM circuitry 1404 a-b may include a WLAN or Wi-Fi FEM circuitry 1404 aand a Bluetooth (BT) FEM circuitry 1404 b. The WLAN FEM circuitry 1404 amay include a receive signal path comprising circuitry configured tooperate on WLAN RF signals received from one or more antennas 1401, toamplify the received signals and to provide the amplified versions ofthe received signals to the WLAN radio IC circuitry 1406 a for furtherprocessing. The BT FEM circuitry 1404 b may include a receive signalpath which may include circuitry configured to operate on BT RF signalsreceived from one or more antennas 1401, to amplify the received signalsand to provide the amplified versions of the received signals to the BTradio IC circuitry 1406 b for further processing. FEM circuitry 1404 amay also include a transmit signal path which may include circuitryconfigured to amplify WLAN signals provided by the radio IC circuitry1406 a for wireless transmission by one or more of the antennas 1401. Inaddition, FEM circuitry 1404 b may also include a transmit signal pathwhich may include circuitry configured to amplify BT signals provided bythe radio IC circuitry 1406 b for wireless transmission by the one ormore antennas. In the embodiment of FIG. 14, although FEM 1404 a and FEM1404 b are shown as being distinct from one another, embodiments are notso limited, and include within their scope the use of an FEM (not shown)that includes a transmit path and/or a receive path for both WLAN and BTsignals, or the use of one or more FEM circuitries where at least someof the FEM circuitries share transmit and/or receive signal paths forboth WLAN and BT signals.

Radio IC circuitry 1406 a-b as shown may include WLAN radio IC circuitry1406 a and BT radio IC circuitry 1406 b. The WLAN radio IC circuitry1406 a may include a receive signal path which may include circuitry todown-convert WLAN RF signals received from the FEM circuitry 1404 a andprovide baseband signals to WLAN baseband processing circuitry 1408 a.BT radio IC circuitry 1406 b may in turn include a receive signal pathwhich may include circuitry to down-convert BT RF signals received fromthe FEM circuitry 1404 b and provide baseband signals to BT basebandprocessing circuitry 1408 b. WLAN radio IC circuitry 1406 a may alsoinclude a transmit signal path which may include circuitry to up-convertWLAN baseband signals provided by the WLAN baseband processing circuitry1408 a and provide WLAN RF output signals to the FEM circuitry 1404 afor subsequent wireless transmission by the one or more antennas 1401.BT radio IC circuitry 1406 b may also include a transmit signal pathwhich may include circuitry to up-convert BT baseband signals providedby the BT baseband processing circuitry 1408 b and provide BT RF outputsignals to the FEM circuitry 1404 b for subsequent wireless transmissionby the one or more antennas 1401. In the embodiment of FIG. 14, althoughradio IC circuitries 1406 a and 1406 b are shown as being distinct fromone another, embodiments are not so limited, and include within theirscope the use of a radio IC circuitry (not shown) that includes atransmit signal path and/or a receive signal path for both WLAN and BTsignals, or the use of one or more radio IC circuitries where at leastsome of the radio IC circuitries share transmit and/or receive signalpaths for both WLAN and BT signals.

Baseband processing circuity 1408 a-b may include a WLAN basebandprocessing circuitry 1408 a and a BT baseband processing circuitry 1408b. The WLAN baseband processing circuitry 1408 a may include a memory,such as, for example, a set of RAM arrays in a Fast Fourier Transform orInverse Fast Fourier Transform block (not shown) of the WLAN basebandprocessing circuitry 1408 a. Each of the WLAN baseband circuitry 1408 aand the BT baseband circuitry 1408 b may further include one or moreprocessors and control logic to process the signals received from thecorresponding WLAN or BT receive signal path of the radio IC circuitry1406 a-b, and to also generate corresponding WLAN or BT baseband signalsfor the transmit signal path of the radio IC circuitry 1406 a-b. Each ofthe baseband processing circuitries 1408 a and 1408 b may furtherinclude physical layer (PHY) and medium access control layer (MAC)circuitry, and may further interface with a device for generation andprocessing of the baseband signals and for controlling operations of theradio IC circuitry 1406 a-b.

Referring still to FIG. 14, according to the shown embodiment, WLAN-BTcoexistence circuitry 1413 may include logic providing an interfacebetween the WLAN baseband circuitry 1408 a and the BT baseband circuitry1408 b to enable use cases requiring WLAN and BT coexistence. Inaddition, a switch 1403 may be provided between the WLAN FEM circuitry1404 a and the BT FEM circuitry 1404 b to allow switching between theWLAN and BT radios according to application needs. In addition, althoughthe antennas 1401 are depicted as being respectively connected to theWLAN FEM circuitry 1404 a and the BT FEM circuitry 1404 b, embodimentsinclude within their scope the sharing of one or more antennas asbetween the WLAN and BT FEMs, or the provision of more than one antennaconnected to each of FEM 1404 a or 1404 b.

In some embodiments, the front-end module circuitry 1404 a-b, the radioIC circuitry 1406 a-b, and baseband processing circuitry 1408 a-b may beprovided on a single radio card, such as wireless radio card 1402. Insome other embodiments, the one or more antennas 1401, the FEM circuitry1404 a-b and the radio IC circuitry 1406 a-b may be provided on a singleradio card. In some other embodiments, the radio IC circuitry 1406 a-band the baseband processing circuitry 1408 a-b may be provided on asingle chip or integrated circuit (IC), such as IC 1412.

In some embodiments, the wireless radio card 1402 may include a WLANradio card and may be configured for Wi-Fi communications, although thescope of the embodiments is not limited in this respect. In some ofthese embodiments, the radio architecture 105A, 105B may be configuredto receive and transmit orthogonal frequency division multiplexed (OFDM)or orthogonal frequency division multiple access (OFDMA) communicationsignals over a multicarrier communication channel. The OFDM or OFDMAsignals may comprise a plurality of orthogonal subcarriers.

In some of these multicarrier embodiments, radio architecture 105A, 105Bmay be part of a Wi-Fi communication station (STA) such as a wirelessaccess point (AP), a base station or a mobile device including a Wi-Fidevice. In some of these embodiments, radio architecture 105A, 105B maybe configured to transmit and receive signals in accordance withspecific communication standards and/or protocols, such as any of theInstitute of Electrical and Electronics Engineers (IEEE) standardsincluding, 802.11n-2009, IEEE 802.11-2012, IEEE 802.11-2016,802.11n-2009, 802.11ac, 802.11ah, 802.11ad, 802.11ay and/or 802.11axstandards and/or proposed specifications for WLANs, although the scopeof embodiments is not limited in this respect. Radio architecture 105A,105B may also be suitable to transmit and/or receive communications inaccordance with other techniques and standards.

In some embodiments, the radio architecture 105A, 105B may be configuredfor high-efficiency Wi-Fi (HEW) communications in accordance with theIEEE 802.11ax standard. In these embodiments, the radio architecture105A, 105B may be configured to communicate in accordance with an OFDMAtechnique, although the scope of the embodiments is not limited in thisrespect.

In some other embodiments, the radio architecture 105A, 105B may beconfigured to transmit and receive signals transmitted using one or moreother modulation techniques such as spread spectrum modulation (e.g.,direct sequence code division multiple access (DS-CDMA) and/or frequencyhopping code division multiple access (FH-CDMA)), time-divisionmultiplexing (TDM) modulation, and/or frequency-division multiplexing(FDM) modulation, although the scope of the embodiments is not limitedin this respect.

In some embodiments, as further shown in FIG. 6, the BT basebandcircuitry 1408 b may be compliant with a Bluetooth (BT) connectivitystandard such as Bluetooth, Bluetooth 8.0 or Bluetooth 6.0, or any otheriteration of the Bluetooth Standard.

In some embodiments, the radio architecture 105A, 105B may include otherradio cards, such as a cellular radio card configured for cellular(e.g., 5GPP such as LTE, LTE-Advanced or 7G communications).

In some IEEE 802.11 embodiments, the radio architecture 105A, 105B maybe configured for communication over various channel bandwidthsincluding bandwidths having center frequencies of about 900 MHz, 2.4GHz, 5 GHz, and bandwidths of about 2 MHz, 4 MHz, 5 MHz, 5.5 MHz, 6 MHz,8 MHz, 10 MHz, 20 MHz, 40 MHz, 80 MHz (with contiguous bandwidths) or80+80 MHz (160MHz) (with non-contiguous bandwidths). In someembodiments, a 920 MHz channel bandwidth may be used. The scope of theembodiments is not limited with respect to the above center frequencieshowever.

FIG. 15 illustrates WLAN FEM circuitry 1404 a in accordance with someembodiments. Although the example of FIG. 15 is described in conjunctionwith the WLAN FEM circuitry 1404 a, the example of FIG. 15 may bedescribed in conjunction with the example BT FEM circuitry 1404 b (FIG.14), although other circuitry configurations may also be suitable.

In some embodiments, the FEM circuitry 1404 a may include a TX/RX switch1502 to switch between transmit mode and receive mode operation. The FEMcircuitry 1404 a may include a receive signal path and a transmit signalpath. The receive signal path of the FEM circuitry 1404 a may include alow-noise amplifier (LNA) 1506 to amplify received RF signals 1503 andprovide the amplified received RF signals 1507 as an output (e.g., tothe radio IC circuitry 1406 a-b (FIG. 14)). The transmit signal path ofthe circuitry 1404 a may include a power amplifier (PA) to amplify inputRF signals 1509 (e.g., provided by the radio IC circuitry 1406 a-b), andone or more filters 1512, such as band-pass filters (BPFs), low-passfilters (LPFs) or other types of filters, to generate RF signals 1515for subsequent transmission (e.g., by one or more of the antennas 1401(FIG. 14)) via an example duplexer 1514.

In some dual-mode embodiments for Wi-Fi communication, the FEM circuitry1404 a may be configured to operate in either the 2.4 GHz frequencyspectrum or the 5 GHz frequency spectrum. In these embodiments, thereceive signal path of the FEM circuitry 1404 a may include a receivesignal path duplexer 1504 to separate the signals from each spectrum aswell as provide a separate LNA 1506 for each spectrum as shown. In theseembodiments, the transmit signal path of the FEM circuitry 1404 a mayalso include a power amplifier 1510 and a filter 1512, such as a BPF, anLPF or another type of filter for each frequency spectrum and a transmitsignal path duplexer 1504 to provide the signals of one of the differentspectrums onto a single transmit path for subsequent transmission by theone or more of the antennas 1401 (FIG. 14). In some embodiments, BTcommunications may utilize the 2.4 GHz signal paths and may utilize thesame FEM circuitry 1404 a as the one used for WLAN communications.

FIG. 16 illustrates radio IC circuitry 1406 a in accordance with someembodiments. The radio IC circuitry 1406 a is one example of circuitrythat may be suitable for use as the WLAN or BT radio IC circuitry 1406a/ 1406 b (FIG. 14), although other circuitry configurations may also besuitable. Alternatively, the example of FIG. 16 may be described inconjunction with the example BT radio IC circuitry 1406 b.

In some embodiments, the radio IC circuitry 1406 a may include a receivesignal path and a transmit signal path. The receive signal path of theradio IC circuitry 1406 a may include at least mixer circuitry 1602,such as, for example, down-conversion mixer circuitry, amplifiercircuitry 1606 and filter circuitry 1608. The transmit signal path ofthe radio IC circuitry 1406 a may include at least filter circuitry 1612and mixer circuitry 1614, such as, for example, up-conversion mixercircuitry. Radio IC circuitry 1406 a may also include synthesizercircuitry 1604 for synthesizing a frequency 1605 for use by the mixercircuitry 1602 and the mixer circuitry 1614. The mixer circuitry 1602and/or 1614 may each, according to some embodiments, be configured toprovide direct conversion functionality. The latter type of circuitrypresents a much simpler architecture as compared with standardsuper-heterodyne mixer circuitries, and any flicker noise brought aboutby the same may be alleviated for example through the use of OFDMmodulation. FIG. 16 illustrates only a simplified version of a radio ICcircuitry, and may include, although not shown, embodiments where eachof the depicted circuitries may include more than one component. Forinstance, mixer circuitry 1614 may each include one or more mixers, andfilter circuitries 1608 and/or 1612 may each include one or morefilters, such as one or more BPFs and/or LPFs according to applicationneeds. For example, when mixer circuitries are of the direct-conversiontype, they may each include two or more mixers.

In some embodiments, mixer circuitry 1602 may be configured todown-convert RF signals 1507 received from the FEM circuitry 1404 a-b(FIG. 14) based on the synthesized frequency 1605 provided bysynthesizer circuitry 1604. The amplifier circuitry 1606 may beconfigured to amplify the down-converted signals and the filtercircuitry 1608 may include an LPF configured to remove unwanted signalsfrom the down-converted signals to generate output baseband signals1607. Output baseband signals 1607 may be provided to the basebandprocessing circuitry 1408 a-b (FIG. 14) for further processing. In someembodiments, the output baseband signals 1607 may be zero-frequencybaseband signals, although this is not a requirement. In someembodiments, mixer circuitry 1602 may comprise passive mixers, althoughthe scope of the embodiments is not limited in this respect.

In some embodiments, the mixer circuitry 1614 may be configured toup-convert input baseband signals 1611 based on the synthesizedfrequency 1605 provided by the synthesizer circuitry 1604 to generate RFoutput signals 1509 for the FEM circuitry 1404 a-b. The baseband signals1611 may be provided by the baseband processing circuitry 1408 a-b andmay be filtered by filter circuitry 1612. The filter circuitry 1612 mayinclude an LPF or a BPF, although the scope of the embodiments is notlimited in this respect.

In some embodiments, the mixer circuitry 1602 and the mixer circuitry1614 may each include two or more mixers and may be arranged forquadrature down-conversion and/or up-conversion respectively with thehelp of synthesizer 1604. In some embodiments, the mixer circuitry 1602and the mixer circuitry 1614 may each include two or more mixers eachconfigured for image rejection (e.g., Hartley image rejection). In someembodiments, the mixer circuitry 1602 and the mixer circuitry 1614 maybe arranged for direct down-conversion and/or direct up-conversion,respectively. In some embodiments, the mixer circuitry 1602 and themixer circuitry 1614 may be configured for super-heterodyne operation,although this is not a requirement.

Mixer circuitry 1602 may comprise, according to one embodiment:quadrature passive mixers (e.g., for the in-phase (I) and quadraturephase (Q) paths). In such an embodiment, RF input signal 1507 from FIG.16 may be down-converted to provide I and Q baseband output signals tobe sent to the baseband processor.

Quadrature passive mixers may be driven by zero and ninety-degreetime-varying LO switching signals provided by a quadrature circuitrywhich may be configured to receive a LO frequency (fLO) from a localoscillator or a synthesizer, such as LO frequency 1605 of synthesizer1604 (FIG. 16). In some embodiments, the LO frequency may be the carrierfrequency, while in other embodiments, the LO frequency may be afraction of the carrier frequency (e.g., one-half the carrier frequency,one-third the carrier frequency). In some embodiments, the zero andninety-degree time-varying switching signals may be generated by thesynthesizer, although the scope of the embodiments is not limited inthis respect.

In some embodiments, the LO signals may differ in duty cycle (thepercentage of one period in which the LO signal is high) and/or offset(the difference between start points of the period). In someembodiments, the LO signals may have an 85% duty cycle and an 80%offset. In some embodiments, each branch of the mixer circuitry (e.g.,the in-phase (I) and quadrature phase (Q) path) may operate at an 80%duty cycle, which may result in a significant reduction is powerconsumption.

The RF input signal 1507 (FIG. 15) may comprise a balanced signal,although the scope of the embodiments is not limited in this respect.The I and Q baseband output signals may be provided to low-noiseamplifier, such as amplifier circuitry 1606 (FIG. 16) or to filtercircuitry 1608 (FIG. 16).

In some embodiments, the output baseband signals 1607 and the inputbaseband signals 1611 may be analog baseband signals, although the scopeof the embodiments is not limited in this respect. In some alternateembodiments, the output baseband signals 1607 and the input basebandsignals 1611 may be digital baseband signals. In these alternateembodiments, the radio IC circuitry may include analog-to-digitalconverter (ADC) and digital-to-analog converter (DAC) circuitry.

In some dual-mode embodiments, a separate radio IC circuitry may beprovided for processing signals for each spectrum, or for otherspectrums not mentioned here, although the scope of the embodiments isnot limited in this respect.

In some embodiments, the synthesizer circuitry 1604 may be afractional-N synthesizer or a fractional N/N+1 synthesizer, although thescope of the embodiments is not limited in this respect as other typesof frequency synthesizers may be suitable. For example, synthesizercircuitry 1604 may be a delta-sigma synthesizer, a frequency multiplier,or a synthesizer comprising a phase-locked loop with a frequencydivider. According to some embodiments, the synthesizer circuitry 1604may include digital synthesizer circuitry. An advantage of using adigital synthesizer circuitry is that, although it may still includesome analog components, its footprint may be scaled down much more thanthe footprint of an analog synthesizer circuitry. In some embodiments,frequency input into synthesizer circuity 1604 may be provided by avoltage controlled oscillator (VCO), although that is not a requirement.A divider control input may further be provided by either the basebandprocessing circuitry 1408 a-b (FIG. 14) depending on the desired outputfrequency 1605. In some embodiments, a divider control input (e.g., N)may be determined from a look-up table (e.g., within a Wi-Fi card) basedon a channel number and a channel center frequency as determined orindicated by the example application processor 1410. The applicationprocessor 1410 may include, or otherwise be connected to, one of theexample secure signal converter 101 or the example received signalconverter 103 (e.g., depending on which device the example radioarchitecture is implemented in).

In some embodiments, synthesizer circuitry 1604 may be configured togenerate a carrier frequency as the output frequency 1605, while inother embodiments, the output frequency 1605 may be a fraction of thecarrier frequency (e.g., one-half the carrier frequency, one-third thecarrier frequency). In some embodiments, the output frequency 1605 maybe a LO frequency (fLO).

FIG. 17 illustrates a functional block diagram of baseband processingcircuitry 1408 a in accordance with some embodiments. The basebandprocessing circuitry 1408 a is one example of circuitry that may besuitable for use as the baseband processing circuitry 1408 a (FIG. 14),although other circuitry configurations may also be suitable.Alternatively, the example of FIG. 16 may be used to implement theexample BT baseband processing circuitry 1408 b of FIG. 14.

The baseband processing circuitry 1408 a may include a receive basebandprocessor (RX BBP) 1702 for processing receive baseband signals 1609provided by the radio IC circuitry 1406 a-b (FIG. 14) and a transmitbaseband processor (TX BBP) 1704 for generating transmit basebandsignals 1611 for the radio IC circuitry 1406 a-b. The basebandprocessing circuitry 1408 a may also include control logic 1706 forcoordinating the operations of the baseband processing circuitry 1408 a.

In some embodiments (e.g., when analog baseband signals are exchangedbetween the baseband processing circuitry 1408 a-b and the radio ICcircuitry 1406 a-b), the baseband processing circuitry 1408 a mayinclude ADC 1710 to convert analog baseband signals 1709 received fromthe radio IC circuitry 1406 a-b to digital baseband signals forprocessing by the RX BBP 1702. In these embodiments, the basebandprocessing circuitry 1408 a may also include DAC 1712 to convert digitalbaseband signals from the TX BBP 1704 to analog baseband signals 1711.

In some embodiments that communicate OFDM signals or OFDMA signals, suchas through baseband processor 1408 a, the transmit baseband processor1704 may be configured to generate OFDM or OFDMA signals as appropriatefor transmission by performing an inverse fast Fourier transform (IFFT).The receive baseband processor 1702 may be configured to processreceived OFDM signals or OFDMA signals by performing an FFT. In someembodiments, the receive baseband processor 1702 may be configured todetect the presence of an OFDM signal or OFDMA signal by performing anautocorrelation, to detect a preamble, such as a short preamble, and byperforming a cross-correlation, to detect a long preamble. The preamblesmay be part of a predetermined frame structure for Wi-Fi communication.

Referring back to FIG. 14, in some embodiments, the antennas 1401 (FIG.14) may each comprise one or more directional or omnidirectionalantennas, including, for example, dipole antennas, monopole antennas,patch antennas, loop antennas, microstrip antennas or other types ofantennas suitable for transmission of RF signals. In some multiple-inputmultiple-output (MIMO) embodiments, the antennas may be effectivelyseparated to take advantage of spatial diversity and the differentchannel characteristics that may result. Antennas 1401 may each includea set of phased-array antennas, although embodiments are not so limited.

Although the radio architecture 105A, 105B is illustrated as havingseveral separate functional elements, one or more of the functionalelements may be combined and may be implemented by combinations ofsoftware-configured elements, such as processing elements includingdigital signal processors (DSPs), and/or other hardware elements. Forexample, some elements may comprise one or more microprocessors, DSPs,field-programmable gate arrays (FPGAs), application specific integratedcircuits (ASICs), radio-frequency integrated circuits (RFICs) andcombinations of various hardware and logic circuitry for performing atleast the functions described herein. In some embodiments, thefunctional elements may refer to one or more processes operating on oneor more processing elements.

The word “exemplary” is used herein to mean “serving as an example,instance, or illustration.” Any embodiment described herein as“exemplary” is not necessarily to be construed as preferred oradvantageous over other embodiments. The terms “computing device,” “userdevice,” “communication station,” “station,” “handheld device,” “mobiledevice,” “wireless device” and “user equipment” (UE) as used hereinrefers to a wireless communication device such as a cellular telephone,a smartphone, a tablet, a netbook, a wireless terminal, a laptopcomputer, a femtocell, a high data rate (HDR) subscriber station, anaccess point, a printer, a point of sale device, an access terminal, orother personal communication system (PCS) device. The device may beeither mobile or stationary.

As used within this document, the term “communicate” is intended toinclude transmitting, or receiving, or both transmitting and receiving.This may be particularly useful in claims when describing theorganization of data that is being transmitted by one device andreceived by another, but only the functionality of one of those devicesis required to infringe the claim. Similarly, the bidirectional exchangeof data between two devices (both devices transmit and receive duringthe exchange) may be described as “communicating,” when only thefunctionality of one of those devices is being claimed. The term“communicating” as used herein with respect to a wireless communicationsignal includes transmitting the wireless communication signal and/orreceiving the wireless communication signal. For example, a wirelesscommunication unit, which is capable of communicating a wirelesscommunication signal, may include a wireless transmitter to transmit thewireless communication signal to at least one other wirelesscommunication unit, and/or a wireless communication receiver to receivethe wireless communication signal from at least one other wirelesscommunication unit.

As used herein, unless otherwise specified, the use of the ordinaladjectives “first,” “second,” “third,” etc., to describe a commonobject, merely indicates that different instances of like objects arebeing referred to and are not intended to imply that the objects sodescribed must be in a given sequence, either temporally, spatially, inranking, or in any other manner.

The term “access point” (AP) as used herein may be a fixed station. Anaccess point may also be referred to as an access node, a base station,an evolved node B (eNodeB), or some other similar terminology known inthe art. An access terminal may also be called a mobile station, userequipment (UE), a wireless communication device, or some other similarterminology known in the art. Embodiments disclosed herein generallypertain to wireless networks. Some embodiments may relate to wirelessnetworks that operate in accordance with one of the IEEE 802.11standards.

Some embodiments may be used in conjunction with various devices andsystems, for example, a personal computer (PC), a desktop computer, amobile computer, a laptop computer, a notebook computer, a tabletcomputer, a server computer, a handheld computer, a handheld device, apersonal digital assistant (PDA) device, a handheld PDA device, anon-board device, an off-board device, a hybrid device, a vehiculardevice, a non-vehicular device, a mobile or portable device, a consumerdevice, a non-mobile or non-portable device, a wireless communicationstation, a wireless communication device, a wireless access point (AP),a wired or wireless router, a wired or wireless modem, a video device,an audio device, an audio-video (A/V) device, a wired or wirelessnetwork, a wireless area network, a wireless video area network (WVAN),a local area network (LAN), a wireless LAN (WLAN), a personal areanetwork (PAN), a wireless PAN (WPAN), and the like.

Some embodiments may be used in conjunction with one way and/or two-wayradio communication systems, cellular radio-telephone communicationsystems, a mobile phone, a cellular telephone, a wireless telephone, apersonal communication system (PCS) device, a PDA device whichincorporates a wireless communication device, a mobile or portableglobal positioning system (GPS) device, a device which incorporates aGPS receiver or transceiver or chip, a device which incorporates an RFIDelement or chip, a multiple input multiple output (MIMO) transceiver ordevice, a single input multiple output (SIMO) transceiver or device, amultiple input single output (MISO) transceiver or device, a devicehaving one or more internal antennas and/or external antennas, digitalvideo broadcast (DVB) devices or systems, multi-standard radio devicesor systems, a wired or wireless handheld device, e.g., a smartphone, awireless application protocol (WAP) device, or the like.

Some embodiments may be used in conjunction with one or more types ofwireless communication signals and/or systems following one or morewireless communication protocols, for example, radio frequency (RF),infrared (IR), frequency-division multiplexing (FDM), orthogonal FDM(OFDM), time-division multiplexing (TDM), time-division multiple access(TDMA), extended TDMA (E-TDMA), general packet radio service (GPRS),extended GPRS, code-division multiple access (CDMA), wideband CDMA(WCDMA), CDMA 2000, single-carrier CDMA, multi-carrier CDMA,multi-carrier modulation (MDM), discrete multi-tone (DMT), Bluetooth®,global positioning system (GPS), Wi-Fi, Wi-Max, ZigBee, ultra-wideband(UWB), global system for mobile communications (GSM), 2G, 2.5G, 3G,3.5G, 4G, fifth generation (5G) mobile networks, 3GPP, long termevolution (LTE), LTE advanced, enhanced data rates for GSM Evolution(EDGE), or the like. Other embodiments may be used in various otherdevices, systems, and/or networks.

The following examples pertain to further embodiments.

Example 1 may include a device comprising processing circuitry coupledto storage, the processing circuitry configured to: establish amulti-link operation with an AP MLD, wherein the AP MLD comprises aplurality of APs within the AP MLD; set up a plurality of links betweenthe AP MLD and the non-AP MLD, wherein the multi-link operation connectson each link of the plurality of links a respective AP of the AP MLDwith a respective device of the non-AP MLD; encode a frame fortransmission on a first link of the plurality of links between a firstAP of the AP MLD and a first STA of the non-AP MLD; identify anindication received at a second STA of the non-AP MLD using aninterference mitigation signal; cause to stop the transmission of theframe on the first link based on the indication; identify a second frameon the first link received from the first AP; and cause to resume thetransmission of the first frame on the first link.

Example 2 may include the device of example 1 and/or some other exampleherein, wherein the processing circuitry may be further configured tocause to send an acknowledgement to the second frame.

Example 3 may include the device of example 1 and/or some other exampleherein, wherein the first frame may include a first preamble and anumber of medium access control (MAC) protocol data units (MPDUs).

Example 4 may include the device of example 1 and/or some other exampleherein, wherein resuming the transmission may include adding a secondpreamble to remaining MPDUs of the first frame.

Example 5 may include the device of example 1 and/or some other exampleherein, wherein the indication may be a stop request and wherein theinterference mitigation signal may be a Zadoff-Chu sequence (ZC)sequence.

Example 6 may include the device of example 1 and/or some other exampleherein, wherein the ZC sequence has a characteristic of z_(i)^(H)z_(j)=0, i≠j.

Example 7 may include the device of example 1 and/or some other exampleherein, wherein the processing circuitry may be further configured toperform cross-correlation to determine that the stop request may beassigned to the first STA.

Example 8 may include the device of example 1 and/or some other exampleherein, wherein the indication may include a packet destined to thesecond STA on the second link.

Example 9 may include the device of example 7 and/or some other exampleherein, wherein the packet may be received on second link withoutstopping transmission on the first link.

Example 10 may include the device of example 1 and/or some other exampleherein, wherein the non-AP MLD may be a non-simultaneous transmitreceive (STR) device.

Example 11 may include a non-transitory computer-readable medium storingcomputer-executable instructions which when executed by one or moreprocessors result in performing operations comprising: establishing amulti-link operation with an AP MLD, wherein the AP MLD comprises aplurality of APs within the AP MLD; setting up a plurality of linksbetween the AP MLD and the non-AP MLD, wherein the multi-link operationconnects on each link of the plurality of links a respective AP of theAP MLD with a respective device of the non-AP MLD; encoding a frame fortransmission on a first link of the plurality of links between a firstAP of the AP MLD and a first STA of the non-AP MLD; identifying anindication received at a second STA of the non-AP MLD using aninterference mitigation signal; causing to stop the transmission of theframe on the first link based on the indication; identifying a secondframe on the first link received from the first AP; and causing toresume the transmission of the first frame on the first link.

Example 12 may include the non-transitory computer-readable medium ofexample 11 and/or some other example herein, wherein the operationsfurther comprise causing to send an acknowledgement to the second frame.

Example 13 may include the non-transitory computer-readable medium ofexample 11 and/or some other example herein, wherein the first frame mayinclude a first preamble and a number of medium access control (MAC)protocol data units (MPDUs).

Example 14 may include the non-transitory computer-readable medium ofexample 11 and/or some other example herein, wherein resuming thetransmission may include adding a second preamble to remaining MPDUs ofthe first frame.

Example 15 may include the non-transitory computer-readable medium ofexample 11 and/or some other example herein, wherein the indication maybe a stop request and wherein the interference mitigation signal may bea Zadoff-Chu sequence (ZC) sequence.

Example 16 may include the non-transitory computer-readable medium ofexample 11 and/or some other example herein, wherein the ZC sequence hasa characteristic of z_(i) ^(H)z_(j)=0, i≠j.

Example 17 may include the non-transitory computer-readable medium ofexample 11 and/or some other example herein, wherein the operationsfurther comprise performing cross-correlation to determine that the stoprequest may be assigned to the first STA.

Example 18 may include the non-transitory computer-readable medium ofexample 11 and/or some other example herein, wherein the indication mayinclude a packet destined to the second STA on the second link.

Example 19 may include the non-transitory computer-readable medium ofexample 11 and/or some other example herein, wherein the non-AP MLD maybe a non-simultaneous transmit receive (STR) device.

Example 20 may include a method comprising: establishing, by one or moreprocessors, a multi-link operation with an AP MLD, wherein the AP MLDcomprises a plurality of APs within the AP MLD; setting up a pluralityof links between the AP MLD and the non-AP MLD, wherein the multi-linkoperation connects on each link of the plurality of links a respectiveAP of the AP MLD with a respective device of the non-AP MLD; encoding aframe for transmission on a first link of the plurality of links betweena first AP of the AP MLD and a first STA of the non-AP MLD; identifyingan indication received at a second STA of the non-AP MLD using aninterference mitigation signal; causing to stop the transmission of theframe on the first link based on the indication; identifying a secondframe on the first link received from the first AP; and causing toresume the transmission of the first frame on the first link.

Example 21 may include the method of example 20 and/or some otherexample herein, further comprising causing to send an acknowledgement tothe second frame.

Example 22 may include the method of example 20 and/or some otherexample herein, wherein the first frame may include a first preamble anda number of medium access control (MAC) protocol data units (MPDUs).

Example 23 may include the method of example 20 and/or some otherexample herein, wherein resuming the transmission may include adding asecond preamble to remaining MPDUs of the first frame.

Example 24 may include the method of example 20 and/or some otherexample herein, wherein the indication may be a stop request and whereinthe interference mitigation signal may be a Zadoff-Chu sequence (ZC)sequence.

Example 25 may include the method of example 20 and/or some otherexample herein, wherein the ZC sequence has a characteristic of z_(i)^(H)z_(j)=0, i≠j.

Example 26 may include the method of example 20 and/or some otherexample herein, further comprising performing cross-correlation todetermine that the stop request may be assigned to the first STA.

Example 27 may include the method of example 20 and/or some otherexample herein, wherein the indication may include a packet destined tothe second STA on the second link.

Example 28 may include the method of example 27 and/or some otherexample herein, wherein the packet may be received on second linkwithout stopping transmission on the first link.

Example 29 may include the method of example 20 and/or some otherexample herein, wherein the non-AP MLD may be a non-simultaneoustransmit receive (STR) device.

Example 30 may include an apparatus comprising means for: establishing amulti-link operation with an AP MLD, wherein the AP MLD comprises aplurality of APs within the AP MLD; setting up a plurality of linksbetween the AP MLD and the non-AP MLD, wherein the multi-link operationconnects on each link of the plurality of links a respective AP of theAP MLD with a respective device of the non-AP MLD; encoding a frame fortransmission on a first link of the plurality of links between a firstAP of the AP MLD and a first STA of the non-AP MLD; identifying anindication received at a second STA of the non-AP MLD using aninterference mitigation signal; causing to stop the transmission of theframe on the first link based on the indication; identifying a secondframe on the first link received from the first AP; and causing toresume the transmission of the first frame on the first link.

Example 31 may include the apparatus of example 30 and/or some otherexample herein, further comprising causing to send an acknowledgement tothe second frame.

Example 32 may include the apparatus of example 30 and/or some otherexample herein, wherein the first frame may include a first preamble anda number of medium access control (MAC) protocol data units (MPDUs).

Example 33 may include the apparatus of example 30 and/or some otherexample herein, wherein resuming the transmission may include adding asecond preamble to remaining MPDUs of the first frame.

Example 34 may include the apparatus of example 30 and/or some otherexample herein, wherein the indication may be a stop request and whereinthe interference mitigation signal may be a Zadoff-Chu sequence (ZC)sequence.

Example 35 may include the apparatus of example 30 and/or some otherexample herein, wherein the ZC sequence has a characteristic of z_(i)^(H)z_(j)=0, i≠j.

Example 36 may include the apparatus of example 30 and/or some otherexample herein, further comprising performing cross-correlation todetermine that the stop request may be assigned to the first STA.

Example 37 may include the apparatus of example 30 and/or some otherexample herein, wherein the indication may include a packet destined tothe second STA on the second link.

Example 38 may include the apparatus of example 37 and/or some otherexample herein, wherein the packet may be received on second linkwithout stopping transmission on the first link.

Example 39 may include the apparatus of example 30 and/or some otherexample herein, wherein the non-AP MLD may be a non-simultaneoustransmit receive (STR) device.

Example 40 may include one or more non-transitory computer-readablemedia comprising instructions to cause an electronic device, uponexecution of the instructions by one or more processors of theelectronic device, to perform one or more elements of a method describedin or related to any of examples 1-39, or any other method or processdescribed herein.

Example 41 may include an apparatus comprising logic, modules, and/orcircuitry to perform one or more elements of a method described in orrelated to any of examples 1-39, or any other method or processdescribed herein.

Example 42 may include a method, technique, or process as described inor related to any of examples 1-39, or portions or parts thereof.

Example 43 may include an apparatus comprising: one or more processorsand one or more computer readable media comprising instructions that,when executed by the one or more processors, cause the one or moreprocessors to perform the method, techniques, or process as described inor related to any of examples 1-39, or portions thereof.

Example 44 may include a method of communicating in a wireless networkas shown and described herein.

Example 45 may include a system for providing wireless communication asshown and described herein.

Example 46 may include a device for providing wireless communication asshown and described herein.

Embodiments according to the disclosure are in particular disclosed inthe attached claims directed to a method, a storage medium, a device anda computer program product, wherein any feature mentioned in one claimcategory, e.g., method, can be claimed in another claim category, e.g.,system, as well. The dependencies or references back in the attachedclaims are chosen for formal reasons only. However, any subject matterresulting from a deliberate reference back to any previous claims (inparticular multiple dependencies) can be claimed as well, so that anycombination of claims and the features thereof are disclosed and can beclaimed regardless of the dependencies chosen in the attached claims.The subject-matter which can be claimed comprises not only thecombinations of features as set out in the attached claims but also anyother combination of features in the claims, wherein each featurementioned in the claims can be combined with any other feature orcombination of other features in the claims. Furthermore, any of theembodiments and features described or depicted herein can be claimed ina separate claim and/or in any combination with any embodiment orfeature described or depicted herein or with any of the features of theattached claims.

The foregoing description of one or more implementations providesillustration and description, but is not intended to be exhaustive or tolimit the scope of embodiments to the precise form disclosed.Modifications and variations are possible in light of the aboveteachings or may be acquired from practice of various embodiments.

Certain aspects of the disclosure are described above with reference toblock and flow diagrams of systems, methods, apparatuses, and/orcomputer program products according to various implementations. It willbe understood that one or more blocks of the block diagrams and flowdiagrams, and combinations of blocks in the block diagrams and the flowdiagrams, respectively, may be implemented by computer-executableprogram instructions. Likewise, some blocks of the block diagrams andflow diagrams may not necessarily need to be performed in the orderpresented, or may not necessarily need to be performed at all, accordingto some implementations.

These computer-executable program instructions may be loaded onto aspecial-purpose computer or other particular machine, a processor, orother programmable data processing apparatus to produce a particularmachine, such that the instructions that execute on the computer,processor, or other programmable data processing apparatus create meansfor implementing one or more functions specified in the flow diagramblock or blocks. These computer program instructions may also be storedin a computer-readable storage media or memory that may direct acomputer or other programmable data processing apparatus to function ina particular manner, such that the instructions stored in thecomputer-readable storage media produce an article of manufactureincluding instruction means that implement one or more functionsspecified in the flow diagram block or blocks. As an example, certainimplementations may provide for a computer program product, comprising acomputer-readable storage medium having a computer-readable program codeor program instructions implemented therein, said computer-readableprogram code adapted to be executed to implement one or more functionsspecified in the flow diagram block or blocks. The computer programinstructions may also be loaded onto a computer or other programmabledata processing apparatus to cause a series of operational elements orsteps to be performed on the computer or other programmable apparatus toproduce a computer-implemented process such that the instructions thatexecute on the computer or other programmable apparatus provide elementsor steps for implementing the functions specified in the flow diagramblock or blocks.

Accordingly, blocks of the block diagrams and flow diagrams supportcombinations of means for performing the specified functions,combinations of elements or steps for performing the specified functionsand program instruction means for performing the specified functions. Itwill also be understood that each block of the block diagrams and flowdiagrams, and combinations of blocks in the block diagrams and flowdiagrams, may be implemented by special-purpose, hardware-based computersystems that perform the specified functions, elements or steps, orcombinations of special-purpose hardware and computer instructions.

Conditional language, such as, among others, “can,” “could,” “might,” or“may,” unless specifically stated otherwise, or otherwise understoodwithin the context as used, is generally intended to convey that certainimplementations could include, while other implementations do notinclude, certain features, elements, and/or operations. Thus, suchconditional language is not generally intended to imply that features,elements, and/or operations are in any way required for one or moreimplementations or that one or more implementations necessarily includelogic for deciding, with or without user input or prompting, whetherthese features, elements, and/or operations are included or are to beperformed in any particular implementation.

Many modifications and other implementations of the disclosure set forthherein will be apparent having the benefit of the teachings presented inthe foregoing descriptions and the associated drawings. Therefore, it isto be understood that the disclosure is not to be limited to thespecific implementations disclosed and that modifications and otherimplementations are intended to be included within the scope of theappended claims. Although specific terms are employed herein, they areused in a generic and descriptive sense only and not for purposes oflimitation.

What is claimed is:
 1. A device for a non-access point (AP) multi-linkdevice (MLD) having a plurality of station devices (STAs), the devicecomprising processing circuitry coupled to storage, the processingcircuitry configured: establish a multi-link operation with an AP MLD,wherein the AP MLD comprises a plurality of APs within the AP MLD; setup a plurality of links between the AP MLD and the non-AP MLD, whereinthe multi-link operation connects on each link of the plurality of linksa respective AP of the AP MLD with a respective device of the non-APMLD; encode a frame for transmission on a first link of the plurality oflinks between a first AP of the AP MLD and a first STA of the non-APMLD; identify an indication received at a second STA of the non-AP MLDusing an interference mitigation signal; cause to stop the transmissionof the frame on the first link based on the indication; identify asecond frame on the first link received from the first AP; and cause toresume the transmission of the first frame on the first link.
 2. Thedevice of claim 1, wherein the processing circuitry is furtherconfigured to cause to send an acknowledgement to the second frame. 3.The device of claim 1, wherein the first frame includes a first preambleand a number of medium access control (MAC) protocol data units (MPDUs).4. The device of claim 1, wherein resuming the transmission includesadding a second preamble to remaining MPDUs of the first frame.
 5. Thedevice of claim 1, wherein the indication is a stop request and whereinthe interference mitigation signal is a Zadoff-Chu sequence (ZC)sequence.
 6. The device of claim 1, wherein the ZC sequence has acharacteristic of z_i{circumflex over ( )}H z_j=0,i≠j.
 7. The device ofclaim 1, wherein the processing circuitry is further configured toperform cross-correlation to determine that the stop request is assignedto the first STA.
 8. The device of claim 1, wherein the indicationincludes a packet destined to the second STA on the second link.
 9. Thedevice of claim 8, wherein the packet is received on second link withoutstopping transmission on the first link.
 10. The device of claim 1,wherein the non-AP MLD is a non-simultaneous transmit receive (STR)device.
 11. A non-transitory computer-readable medium storingcomputer-executable instructions which when executed by one or moreprocessors result in performing operations comprising: establishing amulti-link operation with an AP MLD, wherein the AP MLD comprises aplurality of APs within the AP MLD; setting up a plurality of linksbetween the AP MLD and the non-AP MLD, wherein the multi-link operationconnects on each link of the plurality of links a respective AP of theAP MLD with a respective device of the non-AP MLD; encoding a frame fortransmission on a first link of the plurality of links between a firstAP of the AP MLD and a first STA of the non-AP MLD; identifying anindication received at a second STA of the non-AP MLD using aninterference mitigation signal; causing to stop the transmission of theframe on the first link based on the indication; identifying a secondframe on the first link received from the first AP; and causing toresume the transmission of the first frame on the first link.
 12. Thenon-transitory computer-readable medium of claim 11, wherein theoperations further comprise causing to send an acknowledgement to thesecond frame.
 13. The non-transitory computer-readable medium of claim11, wherein the first frame includes a first preamble and a number ofmedium access control (MAC) protocol data units (MPDUs).
 14. Thenon-transitory computer-readable medium of claim 11, wherein resumingthe transmission includes adding a second preamble to remaining MPDUs ofthe first frame.
 15. The non-transitory computer-readable medium ofclaim 11, wherein the indication is a stop request and wherein theinterference mitigation signal is a Zadoff-Chu sequence (ZC) sequence.16. The non-transitory computer-readable medium of claim 11, wherein theZC sequence has a characteristic of z_i{circumflex over ( )}H z_j=0,i≠j.17. The non-transitory computer-readable medium of claim 11, wherein theoperations further comprise performing cross-correlation to determinethat the stop request is assigned to the first STA.
 18. Thenon-transitory computer-readable medium of claim 11, wherein theindication includes a packet destined to the second STA on the secondlink.
 19. The non-transitory computer-readable medium of claim 11,wherein the non-AP MLD is a non-simultaneous transmit receive (STR)device.
 20. A method comprising: establishing, by one or moreprocessors, a multi-link operation with an AP MLD, wherein the AP MLDcomprises a plurality of APs within the AP MLD; setting up a pluralityof links between the AP MLD and the non-AP MLD, wherein the multi-linkoperation connects on each link of the plurality of links a respectiveAP of the AP MLD with a respective device of the non-AP MLD; encoding aframe for transmission on a first link of the plurality of links betweena first AP of the AP MLD and a first STA of the non-AP MLD; identifyingan indication received at a second STA of the non-AP MLD using aninterference mitigation signal; causing to stop the transmission of theframe on the first link based on the indication; identifying a secondframe on the first link received from the first AP; and causing toresume the transmission of the first frame on the first link.